That hasn't happened in the last 33 Grand Slam events, going back to the 2004 French Open. But here it is: With Nadal sitting out the year's final major tournament with left knee tendinitis, and Federer tossed overboard by 26-year-old Czech Tomas Berdych in Wednesday's quarterfinals, Novak Djokovic theoretically is better positioned to defend his 2011 Open title.
More U.S. Open stories
Or -- gasp! -- the door could be open for only the fifth man (besides Federer, Nadal, Djokovic or 2009 Open champ Juan Martin del Potro) to claim a Slam title in the last 31 majors.
This turn of events "is surprising, in a way," said Serbia's Janko Tipsarevic, who grappled with Ferrer right to the end of their entertaining five-set quarterfinal on Thursday. "I mean, I guess it's good news for the rest of us. We're trying to hopefully, one day, be in a position to win a Grand Slam tournament.
"But, honestly, I don't really know."
Murray (against Berdych) and Djokovic (vs. Ferrer) must be considered the favorites Saturday, based on ranking and overall career success. But Berdych does have a 4-2 head-to-head lead on Murray, and Murray's major-tournament frustrations -- eight years of playing these events without yet fulfilling his championship expectation -- continue to hang in the air.
"You know, I'm still learning and improving with playing those big matches," said Murray, whose Olympic gold-medal victory over Federer seemed to bring the reality of a Slam championship closer. "I have started to understand certain things. Going into Grand Slams, how to go about my business, not just on the court but off, as well.
"You know, conserve energy, go into the matches with the right mind-set and attitude."
Berdych, too, is convinced that experience has made him a better player than the one who lost to Nadal in the Wimbledon final two years ago. "It's another match," Berdych said, "another tournament. So, yeah, it comes."
To Djokovic, whose march to this year's semifinals has been overshadowed by Andy Roddick's retirement party and Federer's upset loss -- even, to some extent, by Nadal's absence -- "it definitely has a special feeling, coming in as a defending champion. It's unique and I love it."
Still, he is wary of potential trouble. Of Ferrer, "one of the biggest competitors we have," Djokovic judged that "people do not talk too much about him. They overlook him. But he has been one of the most consistent players; he plays great on every surface."
A real revolution, then? Maybe led by Ferrer? "I am in the semifinal," he said. "And I am enjoying this moment."